Presently, the removal of human waste and replenishing of lavatory solutions during the servicing of an aircraft is a manual operation. A ramp attendant uses a system of hoses, couplings and storage tanks to drain human waste, including fecal matter, from the aircraft lavatory and to refill the lavatory with a chemical solution, referred to as "blue solution." The blue solution used to fill the storage tanks of the aircraft lavatory generally includes water, perfumes and/or other chemical ingredients that reduce the smell of the human waste. An example of such a mixture is formaldehyde and methanol, which neutralizes the harmful effects of the human waste.
Human waste, whether combined with perfumes or the chemicals used as components of the blue solution, is a hazardous material. Additionally, the blue solution itself is a hazardous material. As such, any contact of human waste or blue solution with human persons, their clothing and other property should be avoided. However, resulting from the apparatus and method due to the consequent lack of protection currently used for servicing aircraft lavatories, there exists the potential for the blue solution and human waste to spill onto the attendant or tarmac during servicing of the aircraft. This spillage may also come into contact with other persons in the vicinity of the aircraft lavatory or with property, such as baggage, which may be associated with the aircraft. Additionally, persons and property may come into contact with blue solution or human waste remaining on an airport tarmac following servicing of an aircraft. Thus, there are significant risks, not the least which are health hazards, for anyone whose person or property contacts the blue solution or human waste.
Regarding the method currently used to service an aircraft lavatory, an attendant places a service cart/truck in proximity to an access panel for the aircraft lavatory. The service cart/truck includes storage tanks that waste will be deposited to and blue solution will be pumped from. The access panel is generally located underneath or on the side of the aircraft. This access panel is usually secured with thumb snaps, which are compressed, allowing the door to open upon release. Following the placement of the service cart/truck, the ramp attendant, wearing latex gloves as a precautionary measure, opens the access panel. Tubing associated with storage tanks of the aircraft lavatory is accessible behind the access panel. Valves are operatively connected to these tubes to effect their opening and closing. The tube and valve system of the aircraft includes a rinse/refill tube having a male flange, a waste tube having a male flange, and a T-handle. By manipulating T-handle, all waste debris inside the holding tank of the aircraft lavatory is released and thus emptied from the aircraft through the waste tube. This waste flows to the storage tank of the service cart/truck through a drain line tube which has been connected to the waste tube of the aircraft. The service cart/truck also includes a refill tube which associates with the rinse/refill tube of the aircraft. These tubes are used to replenish the aircraft lavatory with blue solution once the waste has been discharged.
Generally, upon opening the access panel, a stream of blue solution, which almost always contains human waste, falls out of the drainage pipes in the aircraft. Often, this mixture contacts the hands and clothing of the attendant, the cart/truck and the tarmac underneath the aircraft. Depending on the type and design of the aircraft, any such contamination may spread to the cargo and baggage area near the lavatory system. If wind is blowing during servicing of the aircraft, the potential for spreading of hazardous materials increases significantly.
Following the opening of the access panel, a cap closing off the waste tube is opened. Waste drainage and/or tissue debris is located in the waste tube beyond this cap, as the contents of the lavatory holding tank drain to the lowest point. As in the case of the blue solution, this waste drainage also falls and may contact the attendant's hands, unless the ramp attendant dangerously and quickly releases the handle of the waste cap and steps blindly backwards to avoid the drainage. Such motion could result in accident and/or injury to the attendant and/or others. Occasionally, the waste release valve may have inadvertently been left open or may have opened accidentally during travel, and the waste therein streams out when the ramp attendant opens the cap of the waste tube. This results in a substantial amount of waste debris falling out of the aircraft.
After the initial flow of waste matter has stopped, the attendant will attach the waste coupling on the drain line tube extending from the cart/truck to the aircraft by rotating the head, thereby locking the coupling in place. After locking the waste coupling in place, the attendant releases the waste stored in the lavatory holding tank in order that it may flow into the drain line tube of the now attached waste disposal system. During this flow, human waste and blue solution may leak from the junction of the couplings, the drain line tube and waste tube. Any such leakage causes the exterior of the tubing and coupling to become contaminated. Additionally, this drain line tube lies on top of the service cart/truck, further exposing the entire cart/truck to waste fecal debris. Additionally, any attendant in proximity to the drainage process may come into contact with this waste leakage. The waste debris may further fall to the airport tarmac.
Once the waste has flowed into the drain line tube, the tube must be snaked or angled so the waste will be deposited into the storage tanks of the service cart/truck. As the couplings get more use, the bearings and rings start to wear. As a result, any rotation of the head causes leakage of waste debris. Also the drain line tube generally includes metal wire woven inside. This results in holes and tears in the drain line tube leading to the cart/truck, causing drips and runs as the waste is deposited into the cart/truck.
After the waste is deposited into the cart/truck, the ramp attendant disconnects the waste coupling and steps back quickly and returns the drain line tube and coupling to the cart/truck. The attendant waits until the remaining drips of waste have stopped and then locks the waste cap back in place. This leakage may also result in the contamination of persons and property.
After all waste has been drained from the aircraft, the ramp attendant connects the coupling of the refill tube to the rinse/refill flange of the aircraft and locks it into place in a manner similar to the waste coupling. The attendant walks to the cart/truck and turns on a switch on a pump to refill the lavatory with the blue solution. The amount of blue solution used will vary by aircraft, but can amount up to 25 gallons. Following refill, the attendant stops the pump and unlocks the fill coupling from the aircraft, and, as in the case of the waste drainage, blindly and in a backward motion tries to escape being hit with the refill blue solution as it drains back out of the aircraft. After the backwash flow of the blue solution is emptied onto the tarmac with the attendant hazards of contacting persons and/or property, the agent places the refill tube back onto the cart/truck and locks the cap back onto the rinse/refill tube of the aircraft.
The ramp attendant finally closes the lavatory access panel, and removes the latex gloves and pulls away to the next aircraft. As the ramp attendant pulls away, there is human waste and blue solution left behind on the tarmac and on the cart/truck, as well as on the clothes of the attendant. Waste debris may also remain on the cargo and baggage near the aircraft, and on other persons such as airport personnel. Any waste or blue solution on the tarmac may remain until it rains or the material evaporates.
As can be seen from the above discussion, the current method of servicing aircraft lavatory systems results in the deleterious spread of human waste, such as urine and fecal material, along with blue solution to humans and property. Contact with such hazardous material could potentially have several harmful effects. Thus, it would be desirable to have a system for servicing aircraft lavatories with minimal splashing of human waste onto ramp attendants, property and the tarmac of airports. Additionally, it would be desirable to have a system which minimizes contact of blue solution with attendants, property and the tarmac. Finally, it would be desirable to have a system which would not subject the environment to risks of hazardous materials.